Hard disk drive (HDD) systems typically include one or more data storage disks with concentric tracks containing information. A transducing head carried by a slider is used to read from and write to a data track on one of these disks, wherein each slider has an air bearing surface that is supportable by a cushion of air generated by one of the disks as it is rotating. The slider is carried by an arm assembly that includes an actuator arm and a suspension assembly, which can include a separate gimbal structure or can integrally form a gimbal.
The manufacturing of components of HDD systems often includes providing an electrical connection via solder material between a slider and the transmission lines of the suspension, either by direct connection between such component surfaces, or by connecting bonding pads attached to at least one of the component surfaces. Such a process typically involves depositing a solder ball between bonding pads of a slider and bonding pads of suspension, and then reflowing the solder with a laser beam. As the density of data to be stored on disks continues to increase, more precise positioning and processing of the solder material is becoming increasingly important.
One particular current process for connecting components of an HDD system involves the use of a single square wave laser pulse that is applied to a solder ball, with the amount of laser energy applied by the single pulse being balanced to provide for both the thermal energy for initial melting of the solder sphere as well as the desired amount of thermal energy for reflow of the solder to provide a satisfactory connection between components. The use of such a single high intensity pulse results in the total thermal energy put into the solder sphere occurring in a relatively short time period (typically while still in a capillary and/or shortly after exiting the capillary). This can cause a considerable amount of heat to be conducted into the capillary wall. Additionally, since the reflow energy is put into the solder sphere as thermal energy, the final sphere temperature is far greater than that of the required melt temperature, which can cause an undesirable amount of localized heat to transfer to a slider or other component when it impacts the surface. While a number of other processes are also available, there is a desire to provide additional solder placement techniques that allow for accurate solder connections in high density applications without adverse consequences to the slider, suspension, and/or other HDD system components.